$\left(5-r\right)\left(5-r\right)$

$6.\left(2x-1\right)-7\le-2.\left(5x-2\right)$

$36x^6y^4z^2-64$

$x+2\left(2x^3-8x^2-7x+20\right)$

$\int\sec\left(\frac{x}{2}\right)dx$

$1+\frac{y^2-5y-24}{3y}=\frac{y-6}{3y}$

$\lim_{x\to0}\left(\sin\left(^2\right)\log\left(x\right)\right)$